The general approach required for this initiative will be to first establish a small team of clinical trial sites and subsequently to test identified interventions (pharmacologic and/or non-pharmacologic) in adequately powered Proof of Concept trials in humans. Trials will be initiated after promising interventions are identified by members of the team (including the NIMH Intramural Research Program), and approved by the RAPID steering committee and the NIMH Contracting Officers Technical Representative (COTR) (sometimes also referred to as the Government Program Officer (GPO)). If any compound/intervention identified under this contract or in the field proves to be promising, the Government may choose to conduct a larger efficacy trial with that compound/intervention in lieu of other smaller Proof of Concept trials (see Tasks 4 and 5). All efforts within each task area outlined below will be controlled by task order procedures outlined in more detail in the contract. These procedures require the issuance of a task order request by NIMH, the Contractors response/proposal to a request (including a technical approach and budget), and final NIMH approval to begin the task order. Costs shall not be incurred or reimbursed until a task order has been approved. The approved total cost is a ceiling that cannot be exceeded without further authorization. The emphasis and objective in this contract is to identify and test the most promising interventions for treatment resistant depression (either pharmacologic or non-pharmacologic).